Dental instrument



Aug. 21, 1923.

Filed Jan. 30

ATTORNEYS;

Patented Aug. 21, 1923.

' a UNITED. :s-TA-Tas E W RD EvEnET'r-sMITn, or PH LADE PHIA, rnNNsvLvANIAi Y DENTAL INSTRUM NT, M

. Applicationifiled January 30,1922. Serial. v ssaeu. T

My invention Consists of a dental instrument embodying a hand piece, .a" mandrel with which the tool of the instrument is connected, a bearing memberin which said mandrel ismounted, a driving, shaft adapted to be geared with said 'mandrehand a cap adapted to beoperated by said mandrel corresponding parts in the figures.

and form' a lap-joint with said bearing whereby saliva is prevented from inflowing' to said mandrel and its bearing member i The invention is satisfactorily illustrated in the accompanying drawing, but the im portant instrumentalities thereof may be varied, and so -it is to be understood that v V interfering with the free rotation'of said power trans v the invention is not limited to the specific details shown'and described, as long as they are within the spirit or scope of the claims.

Figure 1 represents a side elevation of a dental instrument embodying my invention.

Figure 2 represents a'longitudinal section thereof.

Figure 3 represents a longitudinal section of certain members thereof in separated con dition, and on an enlarged scale. 7.

Figure t represents vaface view of one, of the gear members of the power or driving shaft of the instrument. Y

Similar numerals of reference indicate Referring to the drawings.

1 designates the vhand piece of a dentalinstrument, in the present 'case," that of 'a grinding device. Mounted 1n the same is the driving shaft 2 which receives power from a suitable engine or motor and carries at its forward end the bevel gear wheel-'3.

To the forward end of said hand piece is screwed or otherwise attached, the sleeve 4-,

which is screwed or otherwise attached to the tubular plug 5 whose bore: forms the bearing for the countershaft or mandrel 6,

whose rear or inner end carries the bevel gear wheel 7 which meshes with the'bevel gear wheel 3, said wheels 3 and? occupying the sleeve 4. 7 4

Secured to the forward or outer end of the plug 5 is the cap 8 of metal or other;

rigidmaterial to whose forward'end is-attached thetubular plug or neck Qalsoof man or other rigid ease against which 1 neck abuts the tool 10, which inthe present case, is that of a stone or grinding disc, it

being noticed o'that the mandrel 6,:exten'ds also through the :bore of said neck l 9,, and

said tool is secured to saidjniandreli 6 by 3 tool into the threaded opening 12 infsaid shaft- 6, thus firmly retaining" the tool in operative position.

the gear wheel 7 meshes with the gear wheel 7 the screw 11 whichfisv passed through-the 3 at a corresponding. angle thereto, without" wheels when the shaft 2 'has mitted to it. 7

.When the sleeve/L parts of the teeth, andso present the tool most 'accessively and conveniently to either 'ofsaid parts of the teeth as maybe desired for the operation of the toolfthereon.

The gear-wheel: 7 i Secured, to thevinnerljb is deflected aszabove it may be: conveniently passed -overyvanous, I

end of the mandrel 6-by the pin or screw 13 which is passed through the hub'of said I V gear wheel and the adjacentportionoflthe mandrel. Then as the cap is connected with the outer end of said mandrel by. the

screw 11 which passes'through the to'olylO and neck 9 of the cap into said mandrelias has been stated, thecap' is retained'on the adjacent portion-of the plug 5- while being adapted to rotate thereon. To assist in retaining the cap on the plug and steady the same in itsrotation, the metal' of the j side of'the cap is'upset' slightly inwardly" as at 14 so that the inner wall, of the upset portion engages :frictionally withthe contiguous part of the plug 5 as a'swivel, with out, however, preventing the free rotation 'of the cap with the tool'and mandreh Then as the forward end and side ofthe plug are shoulder on'the exterior of the plug 5, and

' covered by the neck and side of the cap and the rear end ofthe cap is seated against a flush with the adjacent shoulder 15 on'the 7 exterior ofsaid plug, the joint of the cap and plug is closed whereby sali-va from the mouth is prevented from entering the same and reaching the mandrel, while onthe contrary, the saliva is caused to flow over the exterior of the cap, theexposed portion 5 of the plug, and thehand piece from which it may be readily removed.

Having thus described my invention what I claim as new and desire to secure by Letters Patent, is

1 In a dental instrument of the vcharacter stated, an attachment consisting of a sleeve connectiblewith the hand piece of the instrument, aplug in said sleeve secured thereto, a rotatable cap held on said plug, a neck extending forwardly from said cap and secured thereto and a tool 'carrying mandrel having its bearing in said plug and secured to said neck, said mandrel having on its inner end a gear which is adapted to intermesh with a gear on the driving shaft of the instrument, said neckheing adapted to have the tool abut thereagairist and secured to said mandrel. p

2. In a dental instrument, a -hand-piece, a driving shaft thereimasleev e adapted to be secured to said hand-piece a tubular plug tool of'the instrument being adapted toahut 1 said'necli; 1'

' f I EDWARD.

7T Witnesses:

' JOHN A. WIEDERSHEIM,

N. BUssI-N iiR.

EVERETTs ITH, 

